Q. Hi All,
We currently subcontract our panels for cataphoresis. Recently we have had rejects from our customer with a "marbling/running effect" down to face of the parts. Our supplier is adamant that it is the material which is at fault, but we have checked the material and can find no issue with this whatsoever. Has anybody seen/heard this issue before and found the root cause?

Material is 1 mm thick stainless steel.

Peter Baird - Scotland

December 28, 2012

A. If the raw uncoated steel does not have the same grain pattern as you are seeing over the painted surface, then the paint job or phosphating pretreatment is not good enough.

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